ABSTRACT

As the offshore industry continues to progress developments in deepwater fields, steel catenary risers (SCRs) are often the preferred riser option for subsea tieback to floating platforms. This is due to their conceptual simplicity, ease of construction and installation and simple interface with the flowlines. Modelling of pipesoil interaction in the touchdown zone (TDZ), where the riser meets the seabed, is one of the critical challenges for SCRs, since it has a significant effect on the fatigue life in that zone. The interaction exhibits complex behaviour and is highly nonlinear in response to the random cyclic motions to which the SCR is subjected (Grealish et al. 2007). The pipe-soil interaction in the TDZ is critical for accurate estimation of the fatigue life.